The present invention relates to a chip-forming machine tool provided with a spindlehead having three degrees of freedom, this expression indicating the fact that the spindle can move in space along a set of three Cartesian axes.
More precisely, the invention relates to machine tools in which the rotation axis of the spindle is parallel to an axis of the Cartesian set of three axes, for example the "z" axis, and in which said spindle can move, while maintaining its own rotation axis parallel to the "z" axis, in the direction of two further perpendicular axes "x" and "y" as well as along the direction of said "z" axis.
As known, current machine tools with three degrees of freedom use, for the movement of the spindlehead, a set of three mutually perpendicular sliders which are respectively parallel to the set of three reference axes; said sliders are mutually rigidly associated and can slide with respect to one another.
This known and widespread movement system has several disadvantages, which mostly include its overall bulk, the difficulty in achieving a high degree of precision (since the plays of the various cascade couplings add to one another), and the complexity of the mechanisms for the straight-line movement of the sliders.